I believe the answer is A.
The plasma membrane of the sea urchin egg has receptor molecules that are specific for binding acrosomal proteins .
<h3>What is plasma membrane ?</h3>
Plasma membrane is the outermost covering of the body which selectively permits the entry and exit of different type of materials .
Thus ,it is also called as selectively permeable membrane.it also separates the inner and outer environment of the cell .
It also helps in the diffusion process .
<h3>What are sea urchins ?</h3>
Sea urchins belongs to the animalia kingdom , Echinodermata Phylum, and Echinoidea class . they are small marine animals .Sea urchins are spiny , globular .
Learn more about sea urchins here :
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Answer:
The dark colored moths were due to a genetic mutation, and were more than likely present before the Industrial Revolution. Their fitness was low because predators could easily see them on the light-colored trees. They would be eaten before they could reproduce and pass on their genetic mutation. After the trees became darkened by soot, the darker colored moths now had the survival advantage, able to "hide" from predators. The lighter colored moths became more visible to predators, and the advantage shifted. Now, the light colored moths were more visible to predators, were eaten, and didn't have the chance to reproduce. The darker moths with the mutation had the survival advantage, blending in with the soot-covered trees, and were able to reproduce at higher rates, passing the mutation on to later generations.
The condition of acidosis can also cause hyperkalemia because the higher H+ concentration diffuses to the intracellular fluid, pushing K+ towards the extracellular fluid.
Hyperkalemia describes a potassium level in the blood which is higher than normal. Potassium is a vital substance to the function of nerve and muscle cells, including those of the heart. Blood potassium is normally 3.6 to 5.2 millimoles per liter.
Animals such as sharks have diffrent levels of structres organization in their bodies. each cell in a multicellular organism does not perform every life function